I always like the first commute with a new piece of equipment - it's purely psychological but still real. For me this morning it was the seat post, brand new black Kalloy post from Amazon. It's the basic 1-bolt aluminum post and clamp that weighs and looks the same as any other cheap post but it's kind of a mile-stone since the old one was the last not-new part I had on that bike since I built it back in 2012 I think. It probably "soaks up vibrations" better even if I can't actually feel it ...